Resources
On this page I am happy to share some methodological resources that may be potentially useful to researchers interested in the respective techniques.
Workshop on Moderated Regression
HERE, you can find powerpoint slides from a workshop on moderated regression I was giving at the 2008 EASP summer school in Cardiff. It provides a beginner-oriented overview of how to conduct and interpret moderated regression analyses. Specifically, the workshop covers prototypical cases such as continuous variable by nominal scale interactions and interactions among two continuous predictors. It also addresses questions such as how to compute regression syntax and interpret output from a statistical software program such as SPSS, how to illustrate interaction effects graphically, how to conduct simple slope tests, how to code nominal variables, and how to calculate effect sizes for the interaction effects. Click HERE for a zip-file containing the accompanying spss example data, spss syntax, and excel slides used to illustrate different types of interaction effects.
Extension of Meta-Analysis Macros by David Wilson
The goal of this extension was to make the useful Anova and Regression macros by David Wilson (see Lipsey & Wilson, 2001) somewhat more flexible with regard to a number of data handling and analysis strategies (e.g., outlier exclusion etc.). The computational “core” of the macros by D. Wilson has been left untouched. However, I added some features (click HERE for a more detailed description) that should make the use of both macros easier and less time-consuming. The extenson may be particularly helpful (a) in meta-analyses that involve a larger number of moderators or (b) when the researcher is interested in conducting sensitivity analyses to check how certain variations in the meta-analytic procedure (e.g., fixed vs. random effects, outlier inclusion vs. exclusion) affect the outcome of the meta-analysis. Furthermore, the results will be summarized in .sav and .xls output files. These can be conveniently fed into an Excel-spreadsheet designed to present the results in pre-arranged tables and graphs ready to be exported into other applications.
Download macro package HERE.